The invention concerns a maintenance device for an elongated, tubular hollow body which is configured for conducting a fluid, with a sealing device which is provided for sealing the working region from an environment of the hollow body and can be moved along the hollow body in a direction. The invention further relates to a maintenance device for an elongated, tubular hollow body which is configured for conducting a fluid, in particular with an adapter as part of a sealing device, which adapter can be attached to the hollow body in a sealing manner, has a surface pointing away from the hollow body and jointly forms a working region allowing access to the hollow body, and with a sealing device which is provided for sealing the working region from an environment of the hollow body; and to a method for introducing a maintenance tool into an above-described hollow body for maintaining an elongated, tubular hollow body which is configured for conducting a fluid, with a sealing device being attached to the hollow body in a sealing manner, in such a way that a working region is formed for forming an opening in the hollow body, the working region being sealed by the sealing device from an environment of the hollow body, and the sealing device being movable along the hollow body in a direction. The hollow body is in particular a pipeline for the conducting of for example gas, water or oil.
Tubular hollow bodies, i.e. basically conduits or pipelines, often lie for a long time in inhospitable areas and have to be maintained regularly owing to ageing processes. Access to the pipeline, which is furthermore often earth-laid, is in many cases difficult. There are a number of technologies, by way of which an opening can be formed in a pipeline and by way of which maintenance tools—for example cleaning pigs—can be introduced into the pipeline, for maintaining pipelines of this type, in particular for introducing a maintenance tool into a pipeline.
A device of the aforementioned kind is known from EP 0 935 089 81. This document discloses a device and a method for cutting into a conduit, in which a sealing device in the form of a housing is moved transversely to the longitudinal extension of the conduit and thus along the circumference of the conduit. The device sits tight on the conduit. The housing seals the working space, located between the two device parts which are set apart from each other in the longitudinal direction of the conduit, from an environment of the conduit. The working space or region becomes accessible by opening or removing the housing. The working space is large based on the cross section of the pipeline to be maintained, so that further operation of the conduit without sealing the cut formed in the pipe wall decisively influences the flow in the conduit. In addition, maintenance tools which can be introduced into the line are guided into the line in all cases at an angle and can, precisely owing to the turbulence resulting from the influencing of the flow, easily become jammed in the conduit.
The object of the present invention is to provide a maintenance device and a method for introducing a maintenance access that are improved over the prior art.